1. Field of the Invention
The present invention relates to a portable outdoor gas heater, which can be used in the field. More particularly, the present invention relates to an outdoor gas heater having a backfire arresting function, in which the outdoor gas heater can be prevented from being overheated while losing the heating function due to the backfire, thereby ensuring safety when using the outdoor gas heater.
In addition, the present invention relates to an outdoor gas heater having an anti-fire extinguishing function, capable of preventing the performance degradation caused by the fire extinguishing phenomenon due to the wind and improving the initial ignition performance.
The present invention relates to an outdoor gas heater, which is not shaken when a user manipulates an adjustment handle so that the user can conveniently use the outdoor gas heater.
In addition, the present invention relates to an outdoor gas heater, in which a fire extinguishing safety device, which shuts off fuel gas being fed when the gas heater comes down, is appropriately installed in the outdoor gas heater in such a manner that the volume of the outdoor gas heater can be minimized and the aesthetic appearance of the outdoor gas heater cannot be deteriorated while facilitating the installation work for the fire extinguishing safety device.
2. Description of the Related Art
FIGS. 13 and 14 are perspective views showing a head unit of a gas heater according to the related art.
Referring to FIGS. 13 and 14, the portable outdoor gas heater includes a head unit 100 and a gas feeding unit 200 for feeding fuel gas into a mixing chamber 110 of the head unit 100. The head unit 100 includes the mixing chamber 110 for mixing gas with air, a primary combustion net 120 fixedly coupled to an upper end of the mixing chamber 110 to perform the primary combustion of the gas by controlling the flow of gas supplied to the mixing chamber 110, a secondary combustion net 130 fixedly coupled onto the primary combustion net 120 to perform the secondary combustion of the gas, and a reflective plate 140 fixedly coupled onto the secondary combustion net 130, in which the mixing chamber 110, the primary combustion net 120 and the secondary combustion net 130 are sequentially stacked. In the case of the primary and second combustion nets 120 and 130 of the head unit 100, the primary combustion net 120 has a mesh size smaller than a mesh size of the secondary combustion net 130 for the purpose of heating efficiency and safety. In detail, the mesh size of the secondary combustion net 130 is larger than the mesh size of the primary combustion net 120 by ten times or more.
The outdoor gas heater having the above structure can be conveniently used in the field without causing problems under the 4 mph (min/hour) wind. However, when the wind over 4 mph blows, the wind is infiltrated into the mixing chamber 110 of the head unit 100 by passing through the secondary combustion net 130 and the primary combustion net 120, thereby causing the backfire phenomenon.
That is, since the speed of external air introduced into the mixing chamber 110 is faster than the discharge speed of combustion gas, heat is not emitted to the outside, so that the heater may not perform its original function. If such a backfire phenomenon continues, gas combustion may occur at the lower portion of the mixing chamber or at the region where a nozzle is provided, so that the heater is overheated.
In extreme cases, users may get burned, or the flame spreads so that a fire breaks out.
For this reason, the outdoor gas heater is not available under the strong wind.
In addition, an ignition plug 150 used for auto-ignition and a thermocouple 160 used for detecting combustion heat are provided on the reflective plate 140 above the second combustion net 130, and the thermocouple 160 is connected to a safety valve 230 coupled with a fuel gas inlet tube 210 of a gas feeding unit 200. If the thermocouple 160 detects that combustion heat reaches the predetermined temperature through the stable ignition operation, the safety valve 230 is open to continuously feed the gas. In addition, if the thermocouple 160 detects that the combustion heat falls below the predetermined temperature due to the backfire caused by the wind, the safety valve 230 is closed to shut off the gas being fed, so that automatic fire extinguishing is achieved to ensure safety against the backfire.
However, the outdoor gas heater is mainly used in the field and the thermocouple 160 is exposed out of the head unit 100, so that the thermocouple 160 may be affected by the wind. That is, the thermocouple 160 is easily cooled down when it makes contact with the wind so that the temperature of combustion heat detected by the thermocouple 160 may fall down. For this reason, the fire extinguishing is frequently performed even if the backfire phenomenon does not occur.
Since the fire is frequently extinguished during the use of the gas heater, the user must operate again the gas heater, causing inconvenience to the user.
In addition, the fuel gas inlet tube 210 is coupled to the mixing chamber 110 of the head unit 100 just below the mixing chamber 110, the safety valve 230 coupled with a gas feeding nozzle 220 is coupled to the fuel gas inlet tube 210 just below the fuel gas inlet tube 210, and a connection member 240 is coupled to the safety valve 230 just below the safety valve 230. Further, a fitting unit 250 fitted to a gas container 300 is provided at one side of the connection member 240 and an adjustment handle 260 is provided at the other side of the connection member 240 to adjust the heating power by controlling the amount of gas to be fed.
In order to use the gas heater having the above structure, the fitting unit 250 is fitted into a gas discharge port 310 formed at the upper end of the gas container 300 and the user operates the gas heater by rotating the adjustment handle 260.
However, since the gas heater is supported only by the fitting unit 250 fitted into the gas discharge port 310, the gas heater may be shaken when the user manipulates the adjustment handle 260, thereby causing inconvenience to use the gas heater.
If ignition occurs by operating the adjustment handle 260, the fuel gas is continuously fed through the gas feeding nozzle and the gas heater is continuously operated through the combustion of the fuel gas. However, since the gas heater is mainly installed outside the house, flame may spread if the strong wind blows or the gas heater comes down due to external impact applied thereto, in extreme case, a fire breaks out.
In order to prevent such a dangerous situation, a fire extinguishing safety device is installed in the gas heater to automatically shut off the fuel gas when the gas heater comes down.
However, if the fire extinguishing safety device is installed in the gas heater, the volume of the gas heater is increased so that the aesthetic appearance of the gas heater is deteriorated and the connection work to the gas container is inconvenient. In addition, the ignition work to use the gas heater is difficult and the adjustment handle is not easily manipulated. Therefore, it is necessary to appropriately install the fire extinguishing safety device in the gas heater to solve the above problems and inconvenience.